Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B5/00—Measuring for diagnostic purposes; Identification of persons
  • A61B5/0033—Features or image-related aspects of imaging apparatus classified in A61B5/00, e.g. for MRI, optical tomography or impedance tomography apparatus; arrangements of imaging apparatus in a room
  • A61B5/004—Features or image-related aspects of imaging apparatus classified in A61B5/00, e.g. for MRI, optical tomography or impedance tomography apparatus; arrangements of imaging apparatus in a room adapted for image acquisition of a particular organ or body part
  • A61B5/0042—Features or image-related aspects of imaging apparatus classified in A61B5/00, e.g. for MRI, optical tomography or impedance tomography apparatus; arrangements of imaging apparatus in a room adapted for image acquisition of a particular organ or body part for the brain
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B5/00—Measuring for diagnostic purposes; Identification of persons
  • A61B5/05—Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves 
  • A61B5/055—Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves  involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B5/00—Measuring for diagnostic purposes; Identification of persons
  • A61B5/74—Details of notification to user or communication with user or patient ; user input means
  • A61B5/742—Details of notification to user or communication with user or patient ; user input means using visual displays
  • A61B5/7425—Displaying combinations of multiple images regardless of image source, e.g. displaying a reference anatomical image with a live image
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R33/00—Arrangements or instruments for measuring magnetic variables
  • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
  • G01R33/44—Arrangements or instruments for measuring magnetic variables involving magnetic resonance using nuclear magnetic resonance [NMR]
  • G01R33/48—NMR imaging systems
  • G01R33/50—NMR imaging systems based on the determination of relaxation times, e.g. T1 measurement by IR sequences; T2 measurement by multiple-echo sequences
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R33/00—Arrangements or instruments for measuring magnetic variables
  • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
  • G01R33/44—Arrangements or instruments for measuring magnetic variables involving magnetic resonance using nuclear magnetic resonance [NMR]
  • G01R33/48—NMR imaging systems
  • G01R33/54—Signal processing systems, e.g. using pulse sequences ; Generation or control of pulse sequences; Operator console
  • G01R33/56—Image enhancement or correction, e.g. subtraction or averaging techniques, e.g. improvement of signal-to-noise ratio and resolution
  • G01R33/5602—Image enhancement or correction, e.g. subtraction or averaging techniques, e.g. improvement of signal-to-noise ratio and resolution by filtering or weighting based on different relaxation times within the sample, e.g. T1 weighting using an inversion pulse
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R33/00—Arrangements or instruments for measuring magnetic variables
  • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
  • G01R33/44—Arrangements or instruments for measuring magnetic variables involving magnetic resonance using nuclear magnetic resonance [NMR]
  • G01R33/48—NMR imaging systems
  • G01R33/54—Signal processing systems, e.g. using pulse sequences ; Generation or control of pulse sequences; Operator console
  • G01R33/56—Image enhancement or correction, e.g. subtraction or averaging techniques, e.g. improvement of signal-to-noise ratio and resolution
  • G01R33/561—Image enhancement or correction, e.g. subtraction or averaging techniques, e.g. improvement of signal-to-noise ratio and resolution by reduction of the scanning time, i.e. fast acquiring systems, e.g. using echo-planar pulse sequences
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B2576/00—Medical imaging apparatus involving image processing or analysis
  • A61B2576/02—Medical imaging apparatus involving image processing or analysis specially adapted for a particular organ or body part
  • A61B2576/026—Medical imaging apparatus involving image processing or analysis specially adapted for a particular organ or body part for the brain
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B5/00—Measuring for diagnostic purposes; Identification of persons
  • A61B5/72—Signal processing specially adapted for physiological signals or for diagnostic purposes
  • A61B5/7235—Details of waveform analysis
  • A61B5/7253—Details of waveform analysis characterised by using transforms
  • A61B5/7257—Details of waveform analysis characterised by using transforms using Fourier transforms
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
  • G01R33/00—Arrangements or instruments for measuring magnetic variables
  • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
  • G01R33/44—Arrangements or instruments for measuring magnetic variables involving magnetic resonance using nuclear magnetic resonance [NMR]
  • G01R33/48—NMR imaging systems
  • G01R33/4828—Resolving the MR signals of different chemical species, e.g. water-fat imaging

Definitions

• the present disclosure relates generally to magnetic resonance imaging, and more specifically, to exemplary embodiments of exemplary system, method and computer- accessible medium for accelerated, simultaneous quantitative and non-synthetic multi- contrast imaging.
• qMRI quantitative magnetic resonance imaging
• References 1-5 See, e.g., References 1-5.
• this involves acquiring data from multiple acquisitions to facilitate a regression analysis. This results in prolonged acquisition times, specifically in the case of multi-parametric magnetic resonance imaging (“MRI”) to obtain maps of relaxation (see, e.g., Reference 6), diffusion (see, e.g., References 7 and 8), pharmacokinetic parameters (see, e.g., Reference 8), etc.
• MRI multi-parametric magnetic resonance imaging
• Synthetic MRI in general see, e.g., References 9 and 10
• MRF Magnetic Fingerprinting
• Synthetically generated contrast images can be derived from MRF reconstructed parametric maps.
• it can be challenging to estimate the multitude of phase terms involved in the MR signal equation see, e.g., Reference 13), resulting from diffusion, flow, susceptibility, off-resonance, etc.
• the exemplary system, method, and computer- accessible medium can be used for simultaneous, natural (e.g non-synthetic), multi-contrast and quantitative MR imaging through tailoring of the MRF acquisition schedule
• An exemplary system, method, and computer-accessible medium for generating a particular image which can be a quantitative image(s) of at least one section(s) of a patient(s) or (ii) a non-synthetic contrast image(s) of the section(s) of the patient(s), can include, for example, generating a first magnetic resonance (MR) signal and directing the first MR signal to patient(s), receiving a second MR signal from the patient(s) that can be based on the first MR signal, and generating the particular image(s) based on the second MR signal.
• the first MR signal can be a configured MR signal.
• the configured MR signal can be configured for a particular contrast.
• the first MR signal can have a constant signal intensity.
• the first MR signal can be generated based on a degree of a plurality of flip angles that maintains the constant signal intensity. A degree of flip angles can be selected for the first MR signal based on the particular contrast.
• the degree of the flip angles can vary within a particular range.
• the degree of the flip angles can vary about a mean value.
• the degree of the flip angles can vary monotonously about the mean value.
• the degree of the flip angles can vary pseudo randomly within the particular range.
• the particular range can be about - 5 +/- 4 degrees, about 45 +/- 5 degrees, about 75+/- 5 degrees, or about 75 +/- 5 degrees.
• the particular contrast can include T1, T2, proton density, water, fat, off resonance, diffusion, perfusion, or flow.
• the non-synthetic contrast image(s) can be a non-synthetic multi-contrast image(s).
• the particular image(s) can be generated using a reconstruction procedure.
• the reconstruction procedure can be a sliding window
• the reconstruction procedure can include converting the second MR signal to an image using a Non-Uniform Fast Fourier Transform.
• MR information can be generated based on the second MR signal by pre-processing the second MR sign by compensating for a calibrated gradient delay, scaling k-space of the second MR signal with a ratio of a field of view to a matrix size, removing spikes in the second MR signal, and weighting k-space data in the second MR signal with a predetermined density compensation factor, where the particular image(s) can be generated based on the MR information.
• the particular image(s) can be generated by vector-dot product matching L2-norm normalized dictionary entries with voxel signal evolutions in the second MR signal.
• Figure 1 A is a set of exemplary graphs illustrating a tailored magnetic resonance fingerprint design for TR, FA and TE values according to an exemplary embodiment of the present disclosure
• Figure IB is an exemplary graph illustrating Extended Phase Graph simulations of the magnetic resonance fingerprint acquisition schedules from white matter, gray matter, and cerebrospinal fluid according to an exemplary embodiment of the present disclosure
• Figure 1C is an exemplary graph illustrating Extended Phase Graph simulations for tailored magnetic resonance fingerprint with targeted windows according to an exemplary embodiment of the present disclosure
• Figure ID is an exemplary graph illustrating three voxels for white matter, gray matter and cerebrospinal fluid from a representative magnetic resonance fingerprint acquired in vivo according to an exemplary embodiment of the present disclosure
• Figure IE is an exemplary graph illustrating data voxel plots for tailored magnetic resonance fingerprint according to an exemplary embodiment of the present disclosure
• Figure 2A is a set of exemplary images of a mid-volume slice of four volunteers magnetic resonance fingerprint acquired over 1000 frames according to an exemplary embodiment of the present disclosure
• Figure 2B is a set of exemplary images of tailored magnetic resonance fingerprint depicting proton density contrast and T1 contrast according to an exemplary embodiment of the present disclosure
• Figure 2C is a set of exemplary images of contrast windows according to an exemplary embodiment of the present disclosure.
• Figure 2D is a set of exemplary images of plots for tailored magnetic resonance fingerprint according to an exemplary embodiment of the present disclosure
• Figure 3A is a set of exemplary images of mid-volume slices of four volunteers magnetic resonance fingerprint acquired data for PDw, T1w, T2w and flow Maximum Intensity Projection (“MIP”) at various contrast window frames according to an exemplary embodiment of the present disclosure
• Figure 3B is a set of exemplary images of contrast volumes according to an exemplary embodiment of the present disclosure.
• Figure 3C is a set of exemplary images of tailored magnetic resonance fingerprint contrast windows according to an exemplary embodiment of the present disclosure
• Figure 3D is a set of exemplary images of contrast volumes from tailored magnetic resonance fingerprint according to an exemplary embodiment of the present disclosure
• Figure 4A is a set of exemplary images of mid-volume slices of four volunteers magnetic resonance fingerprint acquired data for proton density, T1, T2 maps according to an exemplary embodiment of the present disclosure
• Figure 4B is a set of volumes depicted by five slices according to an exemplary embodiment of the present disclosure
• Figure 4C is a set of exemplary tailored magnetic resonance fingerprint parametric maps according to an exemplary embodiment of the present disclosure
• Figure 4D is a set of exemplary volumes from tailored magnetic resonance fingerprint acquisition according to an exemplary embodiment of the present disclosure
• Figure 5A is a set of exemplary images of mid-volume slices of four volunteers depicting three regions of interest each for white matter, gray matter and cerebrospinal fluid according to an exemplary embodiment of the present disclosure
• Figure 5B is an exemplary graph illustrating average signal intensity plots for the regions of interest from Figure 5A according to an exemplary embodiment of the present disclosure
• Figure 5C is an exemplary graph illustrating tailored magnetic resonance fingerprint according to an exemplary embodiment of the present disclosure.
• Figure 5D is an exemplary graph illustrating mean and standard deviation for the three regions of interest from Figure 5A for T1 maps according to an exemplary embodiment of the present disclosure
• Figure 5E is an exemplary graph illustrating mean and standard deviation for the three regions of interest from Figure 5A for T2 maps according to an exemplary embodiment of the present disclosure
• Figures 6A-6C are exemplary images of slice(s) of a representative brain data set for three contrasts according to an exemplary embodiment of the present disclosure.
• Figures 7A and 7B are exemplary water-fat images using the exemplary TMRF according to an exemplary embodiment of the present disclosure
• Figures 8 A and 8B are exemplary quantitative images according to an exemplary embodiment of the present disclosure
• Figure 8C is an exemplary graph illustrating the comparison of the mean to standard deviation in each of the contrast blocks according to an exemplary embodiment of the present disclosure
• Figure 9 is a set of exemplary T 1 and T 2 graphs according to an exemplary embodiment of the present disclosure.
• Figure 10 is a set of exemplary reconstructed images according to an exemplary embodiment of the present disclosure.
• Figures 11 A-l II are exemplary images comparing image quality according to an exemplary embodiment of the present disclosure.
• Figure 12 is a flow diagram illustrating an exemplary method for generating a quantitative image of a patient or a non-synthetic contrast image of the patient according to an exemplary embodiment of the present disclosure.
• Figure 13 is an illustration of an exemplary block diagram of an exemplary system in accordance with certain exemplary embodiments of the present disclosure.
• a steady state free precession (“SSFP”) sequence can be provided with a thousand spiral readouts designed to derive unique signal evolutions for different tissue matters.
• MR image contrast derived from such a sequence can be modulated more by the flip angle than the repetition time.
• Figure 1A shows a set of exemplary graphs illustrating a tailored magnetic resonance fingerprint design for TR, FA and TE values according to an exemplary embodiment of the present disclosure.
• Figure IB shows an exemplary graph illustrating Extended Phase Graph simulations of the magnetic resonance fingerprint acquisition schedules from white matter, gray matter, and cerebrospinal fluid according to an exemplary embodiment of the present disclosure.
• MR signal simulation tools such as Extended Phase Graph (“EPG”) (see. e.g., Reference 17)) can be leveraged to vary signal intensities of tissue matters based on their properties (e.g., T 1 , T 2 , etc.) in“blocks” of time. Also, the signal intensities of these tissue matters can remain relatively constant, or slowly varying, if the flip angles were varied smoothly, monotonously, and in a small range within one block.
• Magnetization preparation in the form of an inversion pulse can be efficiently utilized to include suppression of short and long relaxation components like fat and liquids at different temporal points.
• This tissue matter dependent tailored design choice can facilitate different relaxation contrast“windows”, signal constancy in a given contrast window, and a meaningful sliding window reconstructed signal intensity image.
• This exemplary approach referred to as the Tailored MRF (“TMRF”) can retain the MRF derived qMRI benefits of generating multiple parametric maps simultaneously.
• the MRF sequence includes oscillations in flip angle resulting in corresponding fluctuating signal evolutions. Sliding window reconstruction of non-synthetic signal intensity images can be challenging due to the highly undersampled acquisition and the superposition of highly varying signal intensities.
• Exemplary Methods [0044] Exemplary Tailored acquisition design and dictionary generation.
• a one thousand time point (e.g., frames) MRF schedule was used to tailor the magnetization evolution of three tissue types: White Matter (“WM”), Gray Matter (“GM”) and
• Cerebrospinal Fluid This was performed by designing acquisition blocks targeting one or more contrast windows in each block.
• three acquisition blocks for (i) PD and T 1 contrast windows; (ii) T 2 plus flow contrast window; and (iii) T 2 contrast window were generated.
• Each block facilitated a total of 250 frames (e.g. , block size).
• Each block was generated by choosing different Flip Angles (“FA”) with the minimum TR (e.g., 12.8ms) possible: 5° for PD and T 1 , 45° for T 2 and flow, 70° for T 2 weighting. These values were determined based on SSFP literature (see, e.g., References 13, 15 and 16), and EPG simulations.
• FA Flip Angles
• FIG. 1C shows an exemplary graph illustrating Extended Phase Graph simulations for TMRP with targeted windows according to an exemplary embodiment of the present disclosure.
• a 90° pulse was introduced at the 250 th frame (e.g., end of PD and T 1 acquisition block) to facilitate constant signal intensities during the T 2 plus flow contrast window (e.g., shown in boxes 920 in Figure 1C between 250 th to 500 th frame).
• a fourth block included repeated values from the first block. This was performed to match the length of the MRF schedule.
• the values of TE were chosen to be the minimum (e.g., 1.908ms) except in frames between 500 and 625 (e.g., Dixon contrast window). In this contrast window, the TE was increased by 2.2ms to facilitate an out of phase acquisition.
• the resulting TR, FA and TE vectors for the three blocks were concatenated to form the TR/FA/TE schedule.
• FIG. 1A illustrates TR, FA and TE values for the 1000 frame acquisition for MRF (e.g., lines 925) and TMRF (e.g., lines 930), the TR and FA plot depict the acquisition“blocks” of length 250 frames.
• EPG was used to simulate the magnetization evolution dictionary for a range of T 1 (e.g., 0 to 4000ms in steps of 20ms) and T2 (e.g., 0 to 400ms in steps of 20ms; 450 to 600ms in steps of 50ms; 700ms to 2000ms in steps of 500ms) values.
• T 1 e.g., 0 to 4000ms in steps of 20ms
• T2 e.g., 0 to 400ms in steps of 20ms; 450 to 600ms in steps of 50ms; 700ms to 2000ms in steps of 500ms
• the dictionary was then sliding window reconstructed (see, e.g., Reference 18), with a window length of
• Exemplary MR acquisition In vivo brain imaging of four healthy volunteers was performed. Each of the volunteers was scanned with the MRF and TMRF schedules with 20 slices (e.g., for whole brain coverage), slice thickness of 5mm, minimum TR of 12.6 - 12.8ms, field of view 225 - 240mm in each direction with a final matrix size of 256 x 256. The slice planning for both sequences per volunteer were maintained the same to facilitate spatial comparisons. Both sequences leveraged an 89-shot spiral with 608-point readout, maximum gradient strength of 33mT/m and a maximum slew rate of 120T/m/s on a 3T GE 750w scanner using an eight-channel head coil. The resulting acquisition times for the MRF and TMRF cases were 5: 11 and 4:41 (e.g., minute: seconds) respectively.
• Exemplary Reconstruction - quantitative maps L2-norm normalized dictionary entries were vector-dot product matched with the voxel signal evolutions of the contrast images. The index of maximum match was chosen as the key to the dictionary entries for the values of T 1 , T 2 . PD was determined as the ratio of the resulting match (e.g., maximum value) to the norm of the chosen entry. Repeating this process for all voxels provided the spatial maps of the quantitative parameters. The maps from both schedules were compared with the MRF maps as the reference. In addition, Regions-Of-Interest (“ROIs”) were drawn on the central slice of each of the four volunteers. Three ROIs each for WM, GM and CSF were drawn and their mean and standard deviation computed.
• ROIs Regions-Of-Interest
• ROI analysis Three ROIs each corresponding to WM, GM and CSF were manually drawn on the central slices (#9) of the four volunteers.
• the ROI masks were multiplied with the thousand-point time series of contrast images to obtain the mean ROI signal evolution of the three tissue matters for each of the four volunteers for both schedules.
• These ROI masks were also multiplied with the parametric maps to obtain mean T 1 , T 2 and PD values for each volunteer.
• a mean of means was then computed for the T 1 , T 2 values for MRF and the TMRF schedules for the three tissue matters.
• TMRF signal evolutions have blocks of slowly varying magnitude compared to MRF, shown by dashed boxes 920.
• Figure ID illustrates representative sliding window reconstructed signal evolutions from three voxels belonging to three tissue types from a volunteer brain data for the MRF case. Exemplary plots from the corresponding voxel locations for TMRF are shown in Figure IE. The representative voxel data follow the simulation predictions.
• FIG. 2A The sliding window reconstructed central slice for each of the four volunteers for every 100 frames starting with the 10 th frame is shown in Figure 2A.
• Figure 2A shows the mid-volume slice of the four volunteers MRF acquired data over 1000 frames with an interval of 100 frames depicting the changes in contrast over time.
• Figure 2A shows the different, non-synthetic, contrasts that can be derived from TMRF (e.g., frame# 10 - PD; frame # 110 - T 1 weighting with CSF suppression, frame# 610 for T 2 weighting). It also indicates that the signal strengths varied relatively less across the four volunteers in TMRF as compared to MRF.
• TMRF e.g., frame# 10 - PD; frame # 110 - T 1 weighting with CSF suppression, frame# 610 for T 2 weighting
• Figure 2B shows corresponding illustrations for TMRF depicting PD contrast at the 10th frame, T1 contrast at the 110th frame, T2 contrast around the 610th frame (e.g., chosen frame for T2 was 575th) and the effect of the 900 pulse on the sliding window reconstruction shown by arrow 205 on frame 210.
• the exemplary TMRF provides improved contrast for T 1 , PD and T 2 with suppressed flow artifacts (e.g., shown by arrows 210 for the MRF case).
• the CSF suppression and increased contrast can be particularly noticeable in the case of T 1 Fluid Attenuated Inversion Recovery (“FLAIR”)-like weighting (e.g., the first two frames in Figures 2C and 2D).
• FLAIR Fluid Attenuated Inversion Recovery
• Figure 2C shows various contrast windows: five frames of the central slice of the representative MRF data set to depict PD contrast with an interval of ten frames between adjacent images, T1w contrast images of the central slice with an interval of 20 frames, T2w contrast images with an interval of 50 frames, with the arrows 210 depicting unsuppressed CSF and blood flow.
• the relative signal strength of TMRF based T 2 weighting can be higher than T 1 which in turn can be higher than PD (e.g., shown on the same window level of 0 - 250 au. in Figure 2C).
• This trend can be validated by the simulated and observed voxel signal evolutions for the three tissue types in the top and bottom rows of Figure 1C.
• Figure 2D shows corresponding exemplary plots for TMRF data with identical frame intervals within the contrast windows all shown for a signal intensity range between 0 and 250 a.u.
• the SNR of PD weighted (“PDw”) images in TMRF can be lesser than the MRF case (e.g., top rows in Figures 2C and 2D). This can be in line with the simulated response of the TMRF design.
• the PDw images in both cases can be normalized to unit amplitude for better visualization, but was not performed to demonstrate validation of simulation results and comparison of SNR for all three contrasts.
• the T 1 and T 2 weighted images have increased signal strength compared to PD as can be validated by Figures IB and 1C.
• the relative signal strengths between T 1 and T 2 weighted images do not follow a trend as the signal evolution oscillates by design. This also does not facilitate the simple and efficient use of the sliding window reconstruction.
• Figure 3A shows a set of exemplary images of mid-volume slices of four volunteers magnetic resonance fingerprint acquired data for PDw, T1w, T2w and flow Maximum Intensity Projection (“MIP”) at various contrast window frames according to an exemplary embodiment of the present disclosure.
• Figure 3A shows Mid- volume slice of the four volunteers for MRF acquired data for PDw, T1w, T2w and flow MIP at the chosen contrast window frames of 10, 120, 575 and 410.
• Figure 3B depicts the multiple contrasts obtained from specific temporal points for the central slice of the four volunteers and five equally spaces slices (#1, 5, 9, 13, and 17) out of the twenty slices, with an interval of 4 slices between adjacent images for the
• FIG. 3C shows TMRF contrast windows in comparison to MRF data shown in Figure 3A with the additional information of water and uncorrected fat images from frames 450 (in phase) and 575 (out of phase). Arrows 305 show the effect of off-resonance on the uncorrected fat images.
• Figure 3D shows corresponding contrast volumes from TMRF acquisitions for the representative data set.
• the improved CSF suppression with the exemplary TMRF can be attributed to lower flip angles at the beginning of the schedule following the inversion pulse.
• the higher SNR for the MIPs can be attributed to the higher flip angles in the second acquisition block leveraging the recovery of long T 2 components like CSF.
• the MIPs include artifacts, such as capturing information related to eyes and any flow component including CSF rather than blood (e.g., vasculature) alone.
• TMRF panels also show the results of Dixon imaging.
• the TMRF fat images suffer from off-resonance artifacts shown arrows 305 in Figures 3C and 3D.
• FIG. 4A shows mid-volume slices of the four volunteers MRF acquired data for PD, T1, T2 maps.
• Figure 4B shows corresponding volumes depicted by five slices with an interval of 4 slices between adjacent images for the representative data set.
• Figure 4C shows TMRF parametric maps in comparison to MRF data shown in Figure 4A with the additional information of uncorrected Proton Density Fat Fraction (“PDFF”) map including with arrow 405 pointing to the off-resonance artifact.
• PDFF Proton Density Fat Fraction
• Figure 4D shows corresponding exemplary volumes from TMRF acquisitions for the representative data set.
• FIG. 5A The ROIs drawn on the four volunteers for WM (e.g., areas 505), GM (e.g., areas 510) and CSF (e.g., areas 515) are shown in Figure 5A.
• the mean ROI intensity plot over time validated the simulation results shown in Figures 1 A-1E. These curves can also serve as inputs to choose appropriate contrast images in the exemplary TMRF.
• Figure 5B shows an exemplary graph illustrating average signal intensity plots for the regions of interest (e.g., WM 520, GM 525, and CSF 530) from Figure 5A according to an exemplary embodiment of the present disclosure.
• the increased CSF suppression in the first and second acquisition blocks can be seen in Figure 5C.
• the mean ROI values of T 1 for each volunteer is shown as one datum point in Figure 5D, resulting in four data points each for the two schedules.
• the TMRF T 1 values for GM and WM can be higher compared to corresponding MRF values. However, these values can be within the range of T 1 values reported in literature (e.g., Table 1, (see, e.g.. Reference 21)).
• the mean of means and standard deviation are also shown to demonstrate the close grouping of these observations for each schedule.
• Figure 5E shows the corresponding T 2 plots for both schedules.
• the mean ROI values can be closely grouped across volunteers and corresponding values for the two schedules can be similar to one another.
• the TMRF schedule can simultaneously produce five different, natural contrast images and four quantitative maps. This can facilitate collapsing a traditional protocol into a sequence, reduce acquisition time for multiple parametric maps, and provide radiologists contrast windows to pick images from.
• the exemplary TMRF provides a simpler and robust alternative to synthetic MRI approaches that can be used for multiple desired contrasts, measurement based and straightforward to reconstruct and visualize. These acquisitions were included to facilitate a comparison with the thousand frame MRF and subsequent dictionary matching operations. Also, this remainder block can be utilized for other contrast, such as diffusion.
• the inclusion of a 90° pulse at the beginning of the second acquisition block introduced artifacts in sliding window reconstruction, but was utilized to achieve contrast windows in block 2.
• TMRF and MRF schedules can benefit from smoothly varying magnetizations or by eliminating reconstructed images at such transients.
• the relatively slowly changing magnetization evolutions can be leveraged to assign an effective TR, TE and FA to map them to“contrast images” routinely viewed by the radiologist.
• the TRs and FAs can be generated based on the mean/base value in each acquisition block as shown in Figure 1A.
• the TMRF schedule can facilitate inclusion of Dixon imaging. These corrections can be leveraged from demonstrated methods. (See, e.g., Reference 24).
• the choice of FA, TR and TE was based on the knowledge of the tissue matters and contrasts for short TRs.
• An exemplary EPG look ahead procedure (see, e.g., Reference 17), can be utilized to jointly optimize for TMRF contrast between tissue types over time, rather than echo intensities alone.
• Figures 6A-6C show exemplary images of slices of a representative brain data set for three contrasts (e.g., MRF illustrated in Figure 6 A, synthetic images from MRF computed maps shown in Figure 6B, and the exemplary TMRF reconstructions illustrated in Figure 6C) according to an exemplary embodiment of the present disclosure.
• Figure 6C illustrates the choice of the exemplary flip angle in the T1 block that can facilitate suppression of signals from liquids compared to MRF.
• the growth of CSF and other liquid-like matters can be facilitated in the exemplary TMRF providing a maximum intensity projection image depicting flow.
• Figure 6A-6C show that the flow effects can be captured well by the exemplary TMRF.
• TMRF provides for better T1 contrast without flow artifacts (e.g., arrows 605) as compared to the other two contrasts.
• the PD and T2 images from the exemplary TMRF can also suppress flow artifacts compared to MRF.
• the window for all three contrasts are maintained identically in order to compare the relative signal strength for each contrast.
• Figures 7A and 7B show exemplary water-fat images using the exemplary TMRF according to an exemplary embodiment of the present disclosure.
• the top two rows provided in Figure 7A depict the in and out of phase images for one slice over 5 adjacent time points.
• Figure 7B shows these exemplary images for three continuous slices to demonstrate uniform separation across slices.
• the third and fourth rows in Figures 7A and 7B illustrate five frames and the three slices of water and fat images, respectively. These images show the separated fat component along with flow artifacts.
• the bottom row shows the generated temporal and spatial profiles of the proton density fat fraction map. This information related to water-fat imaging demonstrates the flexibility of the exemplary TMRF to include a desired contrast.
• Figures 8A and 8B show exemplary quantitative images according to an exemplary embodiment of the present disclosure.
• Figure 8A shows top map T1 and bottom map T2 over three slices for a representative data set computed using MRF.
• Figure 8B shows the corresponding maps for the exemplary TMRF. It can be observed that both methods can yield similar maps for T1 and T2, which conforms to previously published literature values.
• Figure 8C shows an exemplary graph illustrating the comparison of the mean to standard deviation in each of the contrast blocks according to an exemplary embodiment of the present disclosure.
• the exemplary TMRF provides superior mean to standard deviation for PD and T2. This can also observed in Figures 2A-2D and Figures 6A-6C.
• T1 contrast from the exemplary TMRF has increased contrast but can have lower mean values, which can be attributed to the decreased signal strength seen from TMRF T1 block.
• TMRF generated data was validated and optimized in following two steps during the first six months.
• T 1 and T 2 estimation of the exemplary TMRF was compared to MRF and the Gold Standard (“GS”) measurements at two sites.
• the GS included Spin Echo based measurements of T 1 and T 2 . All data was acquired on ISMRM/NIST (QalibreMD Inc., CO, USA) which has three layers of spheres with a large range of T 1 , T 2 and Proton Density values. For in vitro studies, data for 10 days was acquired on phantom using three methods (e.g., GS, MRF and TMRF) at two sites with the same vendor and field strength (e.g., on GE 3T Discovery 750w).
• GS T 1 and T 2 measurements were conducted using inversion recovery spin echo (“IRSE”) and spin echo (“SE”) sequences. The data were reconstructed and matched with an EPG simulated dictionary. ROI analysis was performed to get T 1 and T 2 estimation for 14 spheres. From the exemplary results, the underestimation of TMRF of long T 1 values can be corrected by a constant bias term.
• site 1 can be close to literature reported values by NIST while site 2 can be close to GS values. The higher order of standard deviation in T 2 values can be due to Bi variations.
• Figure 9 shows the comparison of T 1 map and T 2 map obtained from MRF and TMRF across two sites. MRF and TMRF data were averaged from 10-day repeatability scans.
• the data were obtained from the distinct 14 spheres present in the T 1 and T 2 plates of ISMRM/NIST phantom (QalibreMD Inc., CO, USA).
• a manual ROI analysis was performed on eight datasets. 100 pixels were selected for each sphere in T 1 maps while 70 pixels were selected for T 2 maps due to differences in field of view; MRF and TMRF.
• Figure 10 shows a set of exemplary reconstructed images according to an exemplary embodiment of the present disclosure for the GS, MRF synthetic contrast, TMRF synthetic contrast, and TMRF natural contrasts.
• Each row includes four different contrasts - T 1 weighted, T 1 FLAIR, T 2 weighted and Short T1 inversion Recovery (“STIR”).
• Arrows 1005 and ellipses 1010 in the second and third columns indicate the flow artifacts (e.g ., hyper- intensities or holes) which are not present in the GS and TMRF natural contrast images.
• the gold standard acquired was magnetization prepared T 1 weighted instead of T 1 weighted. All images were acquired on a 3T GE 750w scanner.
• MRF and TMRF studies were performed on 4 normal volunteers. Both methods involved an axial, 20 slice brain coverage with a slice thickness of 5mm, and lmm in plane resolution.
• GS sequences - T 1 weighted, T 1 FLAIR, T 2 weighted and STIR were acquired on the human brain.
• the spatio-temporal profiles of T 1 , T 2 , PD, water-fat and flow contrasts were reconstructed block-wise along with relaxometric maps.
• These MRF and TMRF maps were used to generate the synthetic contrast images using the signal equation and were compared.
• the TMRF natural contrast images were compared with the GS.
• Figure 10 shows the representative images obtained from GS (e.g., natural contrast), MRF (e.g, synthetic contrast) and TMRF (e.g, synthetic and natural contrasts) for the following sequences - magnetization prepared T 1 weighted, T 1 FLAIR, T 2 weighted and STIR.
• GS e.g., natural contrast
• MRF e.g, synthetic contrast
• TMRF synthetic and natural contrasts
• Exemplary EOF Analysis Three ROIs each corresponding to WM, GM and CSF were manually drawn on the central slices (#9). The ROI masks were multiplied with the thousand-point time series of contrast images to obtain the mean ROI signal evolution of the three types of tissue matter for each of the volunteers for both schedules. These ROI masks were also multiplied with the parametric maps to obtain mean T 1 , T 2 and PD values for each volunteer. A mean of means was computed for T 1 , T 2 values for MRF and the TMRF schedules for the three types of tissue matter. The TMRF T 1 values for GM and WM can be higher compared to corresponding MRF values. However, these values can be within the range of T 1 values as reported in literature. The mean ROI values can be closely grouped across volunteers and corresponding values for the two schedules can be similar to one another.
• Figures 1 lA-1 II illustrated exemplary images comparing image quality according to an exemplary embodiment of the present disclosure.
• the synthetically generated images e.g., MRF and TMRF
• the synthetically generated images can be compared with the natural contrast images obtained from GS (see. e.g., Figures 1 lA-1 ID) and the TMRF images produced after sliding window reconstruction as shown in Figures 1 IB-1 ID.
• the magnified version of the edges (e.g., between white matter and gray matter) and the presence/absence of flow artifact are shown in Figures 11E-1I.
• the exemplary GS images can be similar to that of natural contrast obtained from TMRF.
• the data shown here can be representative T 1 FLAIR contrast and the results can be similar to other contrast.
• the exemplary DIXON images obtained from the natural TMRF data do not suppress the water/fat accurately.
• the exemplary system, method and computer-accessible medium can optimize the DIXON method for better suppression of the fat and water. These optimized images can be compared with the LAVA Flex sequence.
• FIG. 11 A The comparison of the image quality between the GS is shown in Figure 11 A, between exemplary synthetic images generated from MRF is shown in Figure G1B, between synthetic images from TMRF is shown in Figure 1 1C, and between natural images obtained after sliding window reconstruction from TMRF is shown in Figure 1 1C.
• Ail illustrated images are T 1 FLAIR contrast.
• a part of the image is magnified (e.g., as shown in the boxes) to see the effect of flow as shown in Figures 11E-1 1G and boundaries between gray matter and white matter, as shown in Figures 11H and 11I.
• Rapid comprehensive MRI exams for example, pediatric neuroimaging, multi- parametric prostate imaging, whole body imaging oncology, diabetes studies inclusive of NASH, study of fat types such as brown, white and brite fat, etc.
• MR value driven protocols for example, 5 -minute stroke protocol, as an alternate to EPImix, MAGIC, etc.
• Multi-scale, multi-modality image fusion e.g., rapid MR-PET exams for
• Figure 12 shows a flow diagram illustrating an exemplary method for generating a quantitative image of a patient or a non-synthetic contrast image of the patient according to an exemplary embodiment of the present disclosure.
• a degree of flip angles for the first MR signal can be selected based on the particular contrast.
• a first magnetic resonance (MR) signal can be generated, which can be directed to the patient.
• a second MR signal can be received from the patient that can be based on the first MR signal.
• the second MR signal can be pre-processed by compensating for a calibrated gradient delay.
• k- space of the second MR signal can be scaled with a ratio of a field of view to a matrix size.
• spikes in the second MR signal can be removed.
• k- space data in the second MR signal can be weighted with a predetermined density compensation factor.
• the particular image can be generated based on the second MR signal, for example, using a reconstruction procedure.
• Figure 13 shows a block diagram of an exemplary embodiment of a system according to the present disclosure.
• exemplary procedures in accordance with the present disclosure described herein can be performed by a processing arrangement and/or a computing arrangement (e.g., computer hardware arrangement) 1305.
• a processing arrangement and/or a computing arrangement e.g., computer hardware arrangement
• processing/computing arrangement 1305 can be, for example entirely or a part of, or include, but not limited to, a computer/processor 1310 that can include, for example one or more microprocessors, and use instructions stored on a computer-accessible medium (e.g., RAM, ROM, hard drive, or other storage device).
• a computer-accessible medium e.g., RAM, ROM, hard drive, or other storage device.
• a computer-accessible medium 1315 e.g., as described herein above, a storage device such as a hard disk, floppy disk, memory stick, CD- ROM, RAM, ROM, etc., or a collection thereol
• the computer-accessible medium 1315 can contain executable instructions 1320 thereon.
• a storage arrangement 1325 can be provided separately from the computer-accessible medium 1315, which can provide the instructions to the processing arrangement 1305 so as to configure the processing arrangement to execute certain exemplary procedures, processes, and methods, as described herein above, for example.
• the exemplary processing arrangement 1305 can be provided with or include an input/output ports 1335, which can include, for example a wired network, a wireless network, the internet, an intranet, a data collection probe, a sensor, etc.
• the exemplary processing arrangement 1305 can be in communication with an exemplary display arrangement 1330, which, according to certain exemplary embodiments of the present disclosure, can be a touch-screen configured for inputting information to the processing arrangement in addition to outputting information from the processing arrangement, for example.
• the exemplary display arrangement 1330 and/or a storage arrangement 1325 can be used to display and/or store data in a user-accessible format and/or user-readable format.
• Weigel M Extended phase graphs: Dephasing, RF pulses, and echoes - pure and simple.

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